////////////////////////////////////////////////////////////
// ============= micro HTML5 library =====================
// @author Gerard Ferrandez / http://www.dhteumeuleu.com/
// last update: May 27, 2013
// Released under the MIT license
// http://www.dhteumeuleu.com/LICENSE.html
////////////////////////////////////////////////////////////

// ===== ge1doot global =====

var ge1doot = ge1doot || {
    json: null,
    screen: null,
    pointer: null,
    camera: null,
    loadJS: function(url, callback, data) {
        if (typeof url == "string") url = [url];
        var load = function(src) {
            var script = document.createElement("script");
            if (callback) {
                if (script.readyState) {
                    script.onreadystatechange = function() {
                        if (script.readyState == "loaded" || script.readyState == "complete") {
                            script.onreadystatechange = null;
                            if (--n === 0) callback(data || false);
                        }
                    }
                } else {
                    script.onload = function() {
                        if (--n === 0) callback(data || false);
                    }
                }
            }
            script.src = src;
            document.getElementsByTagName("head")[0].appendChild(script);
        }
        for (var i = 0, n = url.length; i < n; i++) load(url[i]);
    }
}

// ===== html/canvas container =====

ge1doot.Screen = function(setup) {
    ge1doot.screen = this;
    this.elem = document.getElementById(setup.container) || setup.container;
    this.ctx = this.elem.tagName == "CANVAS" ? this.elem.getContext("2d") : false;
    this.style = this.elem.style;
    this.left = 0;
    this.top = 0;
    this.width = 0;
    this.height = 0;
    this.cursor = "default";
    this.setup = setup;
    this.resize = function() {
        var o = this.elem;
        this.width = o.offsetWidth;
        this.height = o.offsetHeight;
        for (this.left = 0, this.top = 0; o != null; o = o.offsetParent) {
            this.left += o.offsetLeft;
            this.top += o.offsetTop;
        }
        if (this.ctx) {
            this.elem.width = this.width;
            this.elem.height = this.height;
        }
        this.setup.resize && this.setup.resize();
    }
    this.setCursor = function(type) {
        if (type !== this.cursor && 'ontouchstart' in window === false) {
            this.cursor = type;
            this.style.cursor = type;
        }
    }
    window.addEventListener('resize', function() {
        ge1doot.screen.resize();
    }, false);
    !this.setup.resize && this.resize();
}

// ==== unified touch events handler ====

ge1doot.Pointer = function(setup) {
        ge1doot.pointer = this;
        var self = this;
        var body = document.body;
        var html = document.documentElement;
        this.setup = setup;
        this.screen = ge1doot.screen;
        this.elem = this.screen.elem;
        this.X = 0;
        this.Y = 0;
        this.Xi = 0;
        this.Yi = 0;
        this.bXi = 0;
        this.bYi = 0;
        this.Xr = 0;
        this.Yr = 0;
        this.startX = 0;
        this.startY = 0;
        this.scale = 0;
        this.wheelDelta = 0;
        this.isDraging = false;
        this.hasMoved = false;
        this.isDown = false;
        this.evt = false;
        var sX = 0;
        var sY = 0;
        // prevent default behavior
        if (setup.tap) this.elem.onclick = function() { return false; }
        if (!setup.documentMove) {
            document.ontouchmove = function(e) { e.preventDefault(); }
        }
        document.addEventListener("MSHoldVisual", function(e) { e.preventDefault(); }, false);
        if (typeof this.elem.style.msTouchAction != 'undefined') this.elem.style.msTouchAction = "none";

        this.pointerDown = function(e) {
            if (!this.isDown) {
                if (this.elem.setCapture) this.elem.setCapture();
                this.isDraging = false;
                this.hasMoved = false;
                this.isDown = true;
                this.evt = e;
                this.Xr = (e.clientX !== undefined ? e.clientX : e.touches[0].clientX);
                this.Yr = (e.clientY !== undefined ? e.clientY : e.touches[0].clientY);
                this.X = sX = this.Xr - this.screen.left;
                this.Y = sY = this.Yr - this.screen.top + ((html && html.scrollTop) || body.scrollTop);
                this.setup.down && this.setup.down(e);
            }
        }
        this.pointerMove = function(e) {
            this.Xr = (e.clientX !== undefined ? e.clientX : e.touches[0].clientX);
            this.Yr = (e.clientY !== undefined ? e.clientY : e.touches[0].clientY);
            this.X = this.Xr - this.screen.left;
            this.Y = this.Yr - this.screen.top + ((html && html.scrollTop) || body.scrollTop);
            if (this.isDown) {
                this.Xi = this.bXi + (this.X - sX);
                this.Yi = this.bYi - (this.Y - sY);
            }
            if (Math.abs(this.X - sX) > 11 || Math.abs(this.Y - sY) > 11) {
                this.hasMoved = true;
                if (this.isDown) {
                    if (!this.isDraging) {
                        this.startX = sX;
                        this.startY = sY;
                        this.setup.startDrag && this.setup.startDrag(e);
                        this.isDraging = true;
                    } else {
                        this.setup.drag && this.setup.drag(e);
                    }
                } else {
                    sX = this.X;
                    sY = this.Y;
                }
            }
            this.setup.move && this.setup.move(e);
        }
        this.pointerUp = function(e) {
            this.bXi = this.Xi;
            this.bYi = this.Yi;
            if (!this.hasMoved) {
                this.X = sX;
                this.Y = sY;
                this.setup.tap && this.setup.tap(this.evt);
            } else {
                this.setup.up && this.setup.up(this.evt);
            }
            this.isDraging = false;
            this.isDown = false;
            this.hasMoved = false;
            this.setup.up && this.setup.up(this.evt);
            if (this.elem.releaseCapture) this.elem.releaseCapture();
            this.evt = false;
        }
        this.pointerCancel = function(e) {
            if (this.elem.releaseCapture) this.elem.releaseCapture();
            this.isDraging = false;
            this.hasMoved = false;
            this.isDown = false;
            this.bXi = this.Xi;
            this.bYi = this.Yi;
            sX = 0;
            sY = 0;
        }
        if ('ontouchstart' in window) {
            this.elem.ontouchstart = function(e) { self.pointerDown(e); return false; }
            this.elem.ontouchmove = function(e) { self.pointerMove(e); return false; }
            this.elem.ontouchend = function(e) { self.pointerUp(e); return false; }
            this.elem.ontouchcancel = function(e) { self.pointerCancel(e); return false; }
        }
        document.addEventListener("mousedown", function(e) {
            if (
                e.target === self.elem ||
                (e.target.parentNode && e.target.parentNode === self.elem) ||
                (e.target.parentNode.parentNode && e.target.parentNode.parentNode === self.elem)
            ) {
                if (typeof e.stopPropagation != "undefined") {
                    e.stopPropagation();
                } else {
                    e.cancelBubble = true;
                }
                e.preventDefault();
                self.pointerDown(e);
            }
        }, false);
        document.addEventListener("mousemove", function(e) { self.pointerMove(e); }, false);
        document.addEventListener("mouseup", function(e) {
            self.pointerUp(e);
        }, false);
        document.addEventListener('gesturechange', function(e) {
            e.preventDefault();
            if (e.scale > 1) self.scale = 0.1;
            else if (e.scale < 1) self.scale = -0.1;
            else self.scale = 0;
            self.setup.scale && self.setup.scale(e);
            return false;
        }, false);
        if (window.navigator.msPointerEnabled) {
            var nContact = 0;
            var myGesture = new MSGesture();
            myGesture.target = this.elem;
            this.elem.addEventListener("MSPointerDown", function(e) {
                if (e.pointerType == e.MSPOINTER_TYPE_TOUCH) {
                    myGesture.addPointer(e.pointerId);
                    nContact++;
                }
            }, false);
            this.elem.addEventListener("MSPointerOut", function(e) {
                if (e.pointerType == e.MSPOINTER_TYPE_TOUCH) {
                    nContact--;
                }
            }, false);
            this.elem.addEventListener("MSGestureHold", function(e) {
                e.preventDefault();
            }, false);
            this.elem.addEventListener("MSGestureChange", function(e) {
                if (nContact > 1) {
                    if (e.preventDefault) e.preventDefault();
                    self.scale = e.velocityExpansion;
                    self.setup.scale && self.setup.scale(e);
                }
                return false;
            }, false);
        }
        if (window.addEventListener) this.elem.addEventListener('DOMMouseScroll', function(e) {
            if (e.preventDefault) e.preventDefault();
            self.wheelDelta = e.detail * 10;
            self.setup.wheel && self.setup.wheel(e);
            return false;
        }, false);
        this.elem.onmousewheel = function() {
            self.wheelDelta = -event.wheelDelta * .25;
            self.setup.wheel && self.setup.wheel(event);
            return false;
        }
    }
    // ===== request animation frame =====

window.requestAnimFrame = (function() {
    return window.requestAnimationFrame ||
        window.webkitRequestAnimationFrame ||
        window.mozRequestAnimationFrame ||
        window.oRequestAnimationFrame ||
        window.msRequestAnimationFrame ||
        function(run) {
            window.setTimeout(run, 16);
        };
})();
module.exports = { ge1doot }